Baidu: China's Very Own Ghostbuster

By Jocelyn Richards

We see them all the time in China – once pristine apartment buildings now rotting amongst the occasional passing tumbleweed. Known as ‘ghost towns’, these sparse residential lots are the eerie remains of China’s colossal housing boom that took place between 2011 and 2013, which sparked rapid construction and used more cement than the US did in the entire 20th century.

Although China’s inability to fill its endless high-rises has been talked about for years, no one has ever known the precise scale or location of such ghost towns – until now.

Utilizing its ‘Big Data Lab’, researchers from Baidu teamed up with experts at Beijing University to pinpoint China’s forgotten neighborhoods, including those that often go unseen.

The team collected information from Baidu’s 770 million users, which represent a large portion of China’s 1.36 billion inhabitants. By tracking smartphone users who signed onto Baidu between September 2014 and April 2015, the researchers used a common clustering algorithm to calculate their home locations. After matching those addresses with existing residential quarters, the team was able to calculate the urban density of different regions.

So where are these ghostly cities? Baidu isn’t going to rank them, of course, for fear of upsetting an already spooked housing market. But we do know that there are more than 50 ghost cities with fewer than 5,000 people per square kilometer, and that many tend to be in eastern China’s second or third-tier cities.

For a closer look at the results of Baidu’s ghost hunting, click 'Read more' below to visit the Beida/Baidu team site. And the next time you run across paranormal activity, well, you know who to call.

[Images via Reuters/David Gray (apartment photo) and Ghost Cities Analysis Based on Positioning Data in China (map)]